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1.
Rev Soc Bras Med Trop ; 53: e20200680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33331613

RESUMO

INTRODUCTION: The use of insecticide-impregnated dog collars is a potentially useful tool for the control of visceral leishmaniasis. The objective of the present study was to perform a cost-effectiveness analysis of a program based on insecticide-impregnated collars compared to traditional visceral leishmaniasis control strategies used in Brazil. METHODS: A cost-effectiveness analysis was performed from the perspective of the Unified Health System, using data from the Visceral Leishmaniasis Control Program implemented in the municipality of Montes Claros, Minas Gerais. The direct costs of the three control strategies, which were 1) canine infection screening + sacrifice, 2) residual chemical control of the vector, and 3) insecticide-impregnated dog collars (Scalibor®), were evaluated over the two-year study period. RESULTS: The total cost of the program in the area subjected to the traditional control strategies (strategies 1 and 2; control area) was R$ 1,551,699.80, and in the area subjected to all three control strategies (intervention area), it was R$ 1,898,190.16. The collar program was considered highly cost-effective at preventing canine visceral leishmaniasis (incremental cost-effectiveness ratio of approximately R$ 578 per avoided dog sacrifice). CONCLUSIONS: These results provide support for the decision by the Brazilian Ministry of Health in 2019 to provide insecticide-impregnated collars for the control of canine visceral leishmaniasis in a pilot project.


Assuntos
Doenças do Cão , Inseticidas , Leishmaniose Visceral , Piretrinas , Animais , Brasil , Análise Custo-Benefício , Doenças do Cão/prevenção & controle , Cães , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/veterinária , Nitrilos , Projetos Piloto
2.
Rev Soc Bras Med Trop ; 53: e20190421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111904

RESUMO

INTRODUCTION: In Bolivia, before 1982 there were no records of visceral leishmaniasis (VL) cases that would allow us to review and describe the temporospatial occurrence of VL by ecoregions in provinces and departments of Bolivia to evaluate its impact on public health, risk of outbreaks, or dispersion. METHODS: This update on VL in Bolivia is based on research, reviews, and retrospective literature analyses of online data and libraries and institutional reports, from 1939 to the present. RESULTS: In Bolivia, 56 cases of VL have been reported. Until 2014, only three endemic departments had been identified (La Paz, Santa Cruz, and Tarija). Since then, further cases have been recorded in Pando, Cochabamba, and Beni, and in Chuquisaca in 2015. In Yungas, a VL focus was confirmed by isolating and comparing parasites from human and dog cases, and from the Lu. longipalpis vector. VL cases from seven departments, involving 12 different ecoregions were located within the Amazon and Plata basins. CONCLUSIONS: We confirmed that dogs are its primary reservoir, and Lutzomyia longipalpis is its main vector (currently dispersed in six departments). The primary vectors in areas where Lutzomyia longipalpis is absent are Migonemyia migonei and Lutzomyia cruzi.


Assuntos
Leishmaniose Visceral , Psychodidae , Adolescente , Animais , Bolívia/epidemiologia , Brasil , Criança , Pré-Escolar , Cães , Feminino , Humanos , Insetos Vetores , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Masculino , Estudos Retrospectivos , Adulto Jovem
3.
PLoS One ; 15(9): e0238188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32870947

RESUMO

Visceral leishmaniasis caused by the protozoan Leishmania infantum is a zoonosis. The domestic dog is the primary reservoir in urban areas. This study aimed to evaluate the frequency, active infection and load of L. infantum in the genital tract of male and female dogs seropositive for this parasite, as well as to identify histological genital alterations associated with this protozoan. We studied 45 male and 25 female L. infantum-seropositive noncastrated dogs from the same endemic area in Brazil. Tissue samples from the testis, epididymis, prostate, vulva, vagina, and uterus were examined by singleplex qPCR and parasitological tests (histopathology, immunohistochemistry, and parasitological culture). The latter were performed for the detection of active infection (parasites able to multiply and to induce lesions). Forty-four (98%) males and 25 (100%) females were positive for L. infantum in the genital tract (epididymis: 98%; vulva: 92%; vagina: 92%; testis: 91%; uterus: 84%; prostate: 66%). Active infection in the genital tract was confirmed in 69% of males and 64% of females (32% in the uterus). Parasite loads were similar in the testis, vulva, epididymis and vagina and lower in the prostate. Only the parasite load in the vagina was significantly associated with the number of clinical signs. Granulomatous inflammation predominated in all organs, except for the prostate. Only in the testis and epididymis was the inflammatory infiltrate significantly more intense among dogs with a higher parasite load in these organs. The high frequency, detection of active infection and similarity of L. infantum loads in the genital tract of infected males and females suggest the potential of venereal transmission of this parasite by both sexes and of vertical transmission by females in the area studied. Additionally, vertical transmission may be frequent since active L. infantum infection was a common observation in the uterus.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Genitália/parasitologia , Leishmania infantum/fisiologia , Leishmaniose Visceral/veterinária , Animais , Cães , Doenças Endêmicas/veterinária , Feminino , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência
4.
Rev Soc Bras Med Trop ; 53: e20200059, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935780

RESUMO

INTRODUCTION: We sought to determine risk factors (RFs) associated with the presence of antibodies against Leishmania in dogs from a rural area of Ilha Solteira, SP, Brazil. METHODS: Serum samples were collected from 250 dogs and tested using indirect enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody tests (IFATs). Data concerning dogs, their environment, and their owners' knowledge of leishmaniasis were collected using a questionnaire. To determine RFs for contact with the parasite, univariate statistical analysis based on chi-squared and Fisher's exact tests, followed by logistic regression, was used. RESULTS: It was found that 79/250 (31.6%) of the dogs were positive by IFAT, and 72/250 (28.8%) by ELISA. A total of 82/250 dogs (32.8%) were positive in at least one test. The RFs associated with occurrences of Leishmania exposure were large body size (OR = 2.25; 95% CI = 1.26-4.04; p = 0.003), presence of chickens (OR = 1.94; 95% CI = 1.05-3.65; p = 0.023), and lack of knowledge about Leishmania among dog owners (OR = 1.74; 95% CI = 0.96-3.21; p = 0.049). After multivariate analysis, the RFs for occurrence of Leishmania exposure in dogs that remained significantly associated were the dog's size (large dogs) (OR = 1.2; 95% CI = 1.06-1.35; p = 0.003) and presence of chickens on the properties (small farms) (OR = 1.15; 95% CI = 1.02-1.30; p = 0.023). CONCLUSIONS: These results may be useful for improving preventive practices to reduce the incidence of Leishmania exposure among dogs in rural areas.


Assuntos
Doenças do Cão , Leishmania , Leishmaniose Visceral , Animais , Anticorpos Antiprotozoários , Brasil , Galinhas , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Leishmaniose Visceral/veterinária , Masculino , Fatores de Risco
5.
Rev Soc Bras Med Trop ; 53: e20200141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32935783

RESUMO

INTRODUCTION: Canine visceral leishmaniasis (CVL) is an endemic disease in Brazil, and integrated control actions have been adopted by the Brazilian Ministry of Health to control its spread. However, the transmission profile is unknown in areas with recent CVL cases, including Itaúna, located in the Brazilian state of Minas Gerais, where the present study was carried out. METHODS: A total of 2,302 dogs from 12 neighborhoods were serologically tested for canine VL using the current diagnostic protocol adopted by the Brazilian Ministry of Health. Test positivity rate (TPR) and CVL prevalence were determined for each neighborhood. The presence of Leishmania was assessed in 60 seropositive dogs which had been recommended for euthanasia. Twenty-two of them (37%) were asymptomatic, and 38 (63%) were symptomatic for CVL. Parasitological (myeloculture and smear/imprint) and molecular (PCR) methods were employed for Leishmania detection in bone marrow, spleen, mesenteric lymph nodes, and ear skin. The infecting Leishmania species was identified by DNA sequencing. RESULTS: CVL prevalence (per 1,000 dogs) varied from 0.0-166.67, depending on the neighborhood, with a mean of 68.96 (SD 51.38). Leishmania DNA was detected in at least one tissue from all seropositive dogs, with comparable TPR among tissues. Leishmania parasites were identified in most (54/60) seropositive dogs, and the infecting parasite was identified as Leishmania infantum in all of these. CONCLUSIONS: Prevalence of CVL is a contributor to the spread of visceral leishmaniasis in Itaúna.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Brasil , Cães , Feminino , Leishmaniose Visceral/veterinária , Masculino , Prevalência
6.
PLoS One ; 15(9): e0238601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881961

RESUMO

Canines are proven reservoir hosts of Leishmania infantum, the causative agent of human zoonotic visceral leishmaniasis, and therefore domestic dogs play a central role in transmitting the disease to humans. Studies on the effect of insecticide-impregnated dog collars for controlling canine visceral leishmaniasis (CanL) have been increasing; however, meta-analysis has not been conducted. This study assessed the effectiveness of insecticide-impregnated dog collars for preventing CanL. We searched (PubMed, Web of Science, Scopus, Embase, Ovid Medline(R), and Cochrane library), from inception until 2 May 2020. Two authors independently performed articles screening and data extraction. We applied the RoB 2.0 tool to evaluate the risk of bias in randomized trials, while the ROBINS-I tool was used for non-randomized trials. I-squared statistics(I2) and funnel plot and Egger's test, respectively, were used to assesses heterogeneity between studies and publication bias. Relative Risk (RR) and 95% Confidence Interval (CI) were calculated using the random-effects model in Stata 14 software. Out of 242 citations identified, 14 studies comprising 3786 collared dogs and 3428 uncollared dogs were eligible for meta-analysis. The use of deltamethrin-impregnated dog collars(DMC) showed an overall effectiveness of 54% (95%CI: 35-65%, I2 = 63.2%, P = 0.002) in decreasing incidence of CanL, while 10% imidacloprid and 4.5% flumethrin collars provided an overall effectiveness of 90% (95%CI: 80-96%, I2 = 0.0%, P = 0.376). DMC efficacy stratified by follow-up duration was estimated to be 58% (RR = 0.42, 95%CI: 0.20-0.87), 54% (RR = 0.46, 95%CI: 0.31-0.68), 53% (RR = 0.47, 95%CI: 0.29-0.82) for follow-up periods of 5 to 6 months, 1 year and 2 years, respectively. The current evidence indicates that using insecticide-impregnated dog collars can reduce the risk of CanL caused by L. infantum. Therefore, insecticide-impregnated dog collars could be a viable alternative for inclusion as a public health measure for controlling CanL.


Assuntos
Doenças do Cão/prevenção & controle , Inseticidas/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/prevenção & controle , Administração Cutânea , Animais , Doenças do Cão/parasitologia , Cães , Leishmaniose Visceral/veterinária , Neonicotinoides/farmacologia , Nitrilos/farmacologia , Nitrocompostos/farmacologia , Piretrinas/farmacologia
7.
Acta Vet Scand ; 62(1): 42, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746875

RESUMO

Canine vector-borne diseases are caused by pathogens transmitted by arthropods including ticks, mosquitoes and sand flies. Many canine vector-borne diseases are of zoonotic importance. This study aimed to assess the prevalence of vector-borne infections caused by Dirofilaria immitis, Ehrlichia canis, Borrelia burgdorferi sensu lato, Anaplasma spp. and Leishmania infantum in a dog kennel in Argeș County, Romania. Dog kennels are shelters for stray dogs with no officially registered owners that are gathered to be neutered and/or boarded for national/international adoptions by various public or private organizations. The international dog adoptions might represent a risk in the transmission of pathogens into new regions. In this context, a total number of 149 blood samples and 149 conjunctival swabs from asymptomatic kennel dogs were assessed using serology and quantitative real-time polymerase chain reaction. Antibodies against B. burgdorferi s.l. were detected in one dog (0.6%), anti-Anaplasma antibodies were found in five dogs (3.3%), while ten dogs (6.7%) tested positive for D. immitis antigen. Overall, 20.1% (30/149) of dogs were positive for L. infantum DNA. All samples were seronegative for anti-Leishmania antibodies. When adopting dogs from this region of Romania, owners should be aware of possible infection with especially L. infantum. The travel of infected dogs may introduce the infection to areas where leishmaniasis is not present.


Assuntos
Anaplasmose/epidemiologia , Doenças do Cão/epidemiologia , Ehrlichiose/veterinária , Leishmaniose Visceral/veterinária , Doença de Lyme/veterinária , Anaplasma/isolamento & purificação , Anaplasmose/microbiologia , Animais , Anticorpos Antibacterianos/análise , Borrelia burgdorferi/isolamento & purificação , DNA de Protozoário/análise , Vetores de Doenças , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia canis/isolamento & purificação , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Feminino , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Masculino , Prevalência , Romênia/epidemiologia
8.
Parasitol Res ; 119(10): 3541-3548, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32803333

RESUMO

The aim of this study was to evaluate, through qPCR, the prevalence of parasitemia in sick kennel dogs naturally infected by canine leishmaniasis. An evaluation of daily changes of the parasitic load in peripheral blood was also performed. A comprehensive clinical examination and the collection of several samples (blood, lymph node, skin, and conjunctiva) were performed in 140 dogs living in an endemic area. Among these, only the dogs with clinically evident leishmaniasis were enrolled (39/140; 27.9%). Twelve (30.8%) out of 39 showed parasitemia, with a low load (median: 4 Leishmania/ml) despite a high lymph node parasite load (median: 4000 Leishmania/ml) and high IFAT titers (≥ 1:640). Seven sick dogs were sampled every 4 h for 6 times during a 24-h period, in order to obtain light- and dark-span samples. Only one (14.3%) out of the seven serial sampled dogs showed Leishmania DNA in the peripheral blood in two samples (2/42; 4.8%). Surprisingly, Leishmania DNA was also detected in the peripheral blood of asymptomatic dogs, negative to both serology and PCR performed on samples other than blood (6/101; 5.9%). The present study confirms that in canine leishmaniasis parasitemia is uncommon and even transitory. Even if recommended, microscopic examination is confirmed as a low sensitivity method with a lower diagnostic utility in canine leishmaniasis than qPCR. Moreover, circulating Leishmania DNA can be found even in healthy dogs. This finding is important in clinical practice because in endemic areas it suggests a transfusion risk and a possible transmission to the vector.


Assuntos
Doenças do Cão/parasitologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/veterinária , Parasitemia/veterinária , Animais , DNA de Protozoário/sangue , DNA de Protozoário/genética , Doenças do Cão/epidemiologia , Cães , Leishmania infantum/genética , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Carga Parasitária/veterinária , Parasitemia/epidemiologia , Parasitemia/parasitologia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária
9.
PLoS Negl Trop Dis ; 14(7): e0008488, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716931

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a major neglected disease, potentially fatal, whose control is still impaired by inefficient and/or expensive treatment and diagnostic methods. The most promising approach for VL diagnosis uses serological assays with recombinant proteins, since they are more efficient and easier to perform. Tests developed for the human form of the disease, however, have not been shown to be efficient for its diagnosis in the canine host, the major reservoir for the American VL. METHODOLOGY/PRINCIPAL FINDINGS: Here, we describe a systematic approach aimed at the production of a new chimeric protein potentially able to be used for both human and canine VL diagnosis and based both on in silico gene design and experimental data. Starting from the previous identification of Leishmania infantum recombinant antigens efficient for the diagnosis of either human or canine VL, three of the best performing antigens were selected (Lci2, Lci3 and Lci12). After a preliminary evaluation validating the chimeric approach, DNA fragments encoding predicted antigenic regions from each protein, enriched with repeats, were joined in various combinations to generate a total of seventeen chimeric genes optimized for prokaryotic expression. These were assessed for optimal expression and purification yield, with four chimeric proteins being efficiently produced. Their diagnostic potential was then evaluated through ELISA assays with sera from VL afflicted humans and dogs. After two rounds of gene design, the results showed high levels of sensitivity for the best chimeric protein, named Q5, in humans (82%) and dogs (100%) with 100% specificity in comparison with healthy controls. A single non-specific reaction was seen with serum from individuals with tegumentary leishmaniasis. CONCLUSION: The newly described chimeric protein is potentially useful for the detection of both humans and dogs afflicted with VL, with its use in rapid tests necessary for validation as a new diagnostic tool.


Assuntos
Doenças do Cão/diagnóstico , Leishmaniose Visceral/veterinária , Testes Sorológicos/veterinária , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Doenças do Cão/sangue , Cães , Escherichia coli/metabolismo , Regulação da Expressão Gênica , Humanos , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Transcriptoma
10.
PLoS Negl Trop Dis ; 14(7): e0007986, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716941

RESUMO

Genetic polymorphisms in natural Leishmania populations have been reported in endemic areas. Microsatellite typing is a useful tool to elucidate the genetic variability of parasite strains, due to its capability for high-resolution mapping of genomic targets. The present study employed multilocus microsatellite typing (MLMT) to explore the genotypic composition of Leishmania infantum in naturally infected dogs by genotyping parasites infecting different tissues with or without in vitro expansion. Eighty-six samples were collected from 46 animals in an endemic region of visceral leishmaniasis (VL). MLMT was performed for 38 spleen samples and 48 L. infantum cultures isolated from different tissues. Of the 86 samples, 23 were effectively genotyped by MLMT, identifying nine multilocus genotypes (MLG; referred to as MLG A-I). MLGs A, B and C were detected in more than one type of tissue and in more than one sample. Conversely, MLG D-I were uniquely detected in one sample each. The results showed that multiple genotype infections occur within a single host and tissue. Paired sample analysis revealed the presence of different MLMT alleles in 14 dogs, while the same MLG allele was present in 15 animals. STRUCTURE analysis demonstrated the presence of two populations; 13 samples displayed a similar admixture of both ancestral populations, and these were not assigned to any population. Only samples for which Q ≥ 0.70 after CLUMPP alignment were considered to be part of Population 1 (POP1) or Population 2 (POP2). POP2 comprised the majority of samples (n = 54) compared to POP1 (n = 19). This study presents evidence of multiple genotype infections (caused by L. infantum) in dogs in an area with high VL transmission. Further investigations must be undertaken to determine the effects of multiple infection on the host immune response and disease dynamics and treatment.


Assuntos
Doenças do Cão/parasitologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/veterinária , Animais , Cães , Feminino , Variação Genética , Genótipo , Leishmania infantum/classificação , Leishmania infantum/genética , Leishmaniose Visceral/parasitologia , Masculino , Repetições de Microssatélites , Filogenia
11.
PLoS One ; 15(7): e0236127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32692783

RESUMO

Visceral leishmaniasis (VL) is an important zoonosis in Brazil. Dogs are considered the main domestic reservoirs of the disease in the country; hence, control measures are focused on these reservoirs. Despite efforts to prevent and control VL, important reductions in disease prevalence and incidence have not been identified, stimulating the development and application of new strategies. The choice and implementation of new control strategies can benefit from the application of mathematical models that allow the simulation of different strategies in different scenarios. Selecting the best strategy to be implemented is also supported by cost-effectiveness studies. Here we used the results of a mathematical model in which scenarios, including isolated use of the vaccine and insecticide-impregnated collar (IIC), both at different coverage rates, were simulated to conduct a cost-effectiveness study. The costs were calculated for each scenario considering a simulation period of four years. Collar application in both infected and non-infected animals was the most cost-effective strategy. For example, to reduce the prevalence in humans and dogs by approximately 70%, the costs ranged from $250,000 and $550,000 for the IICs and vaccination, respectively. Even in the scenario with 40% loss/replacement of IICs, this measure was more advantageous in terms of cost-effectiveness than vaccination. If the vaccine were applied with culling of seropositive tested dogs, then the measure became more effective with a reduced cost compared with the vaccine alone. The use of the three first consecutive vaccine doses had the greatest impact on the cost of the vaccination strategy. The advantage of using IICs is that there is no need for a prior diagnosis, unlike vaccination, reducing costs and facilitating implementation. The present study aims to contribute to strategies to reduce hosts infected with VL by reducing public expenditure.


Assuntos
Doenças do Cão/economia , Doenças do Cão/prevenção & controle , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/economia , Leishmaniose Visceral/prevenção & controle , Vacinação/economia , Vacinação/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Leishmania donovani/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Prevalência
12.
Exp Parasitol ; 217: 107947, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32628971

RESUMO

Visceral leishmaniasis (VL) is an infectious disease caused by the protozoan parasite Leishmania (Leishmania) infantum, an intracytoplasmic parasite that affects humans and other species of domestic and wild mammals. In Brazil, the treatment of canine visceral leishmaniasis (CVL) with miltefosine has been implemented since 2016, and the reports on the clinical and immunological conditions of treated dogs are scarce. Thus, this study aimed to assess and monitor the clinical, laboratory, and immunological condition of dogs with CVL before (D0) and after (D29) using three pharmacotherapeutic protocols: miltefosine monotherapy (Milteforan™, Virbac) (G1), miltefosine plus allopurinol (G2), and allopurinol monotherapy (G3). Forty-five dogs with CVL were assigned to one of three treatment groups. The dogs were evaluated for clinical signs, was well as haematological, biochemical, serological, and cytokine levels. Significant reduction in clinical scores was observed in all protocols, with no differences between groups. We did not observe a clinical cure in any of the dogs in the groups. Haematological and biochemical parameters showed slow recovery, with better results observed in G2. Anti-Leishmania antibody titre remained increased in all groups. The quantification of serum cytokines demonstrated a mixed Th1/Th2 profile in CVL. The IL-2 levels decreased in all groups after treatment. Evaluation of IFN-y and IL-10 did not show changes in the groups analysed, and it did not contribute to short term therapeutic monitoring. All therapeutic protocols promoted, to varying degrees, an improvement in the general condition (clinical signs, haematological, and biochemical levels) of the animals. Through clinical-pathological exams, we found that the combination of miltefosine plus allopurinol promoted better effects in the short-term, representing the best choice for the treatment of CVL, even when compared to the only therapeutic protocol allowed in Brazil, miltefosine monotherapy. Through the quantification of cytokines, IL-2 proved to be a potential therapeutic marker for the monitoring and follow-up of dogs with CVL.


Assuntos
Alopurinol/uso terapêutico , Antiprotozoários/uso terapêutico , Doenças do Cão/tratamento farmacológico , Leishmaniose Visceral/veterinária , Fosforilcolina/análogos & derivados , Animais , Citocinas/sangue , Doenças do Cão/parasitologia , Cães , Quimioterapia Combinada , Feminino , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Masculino , Fosforilcolina/uso terapêutico
13.
Exp Parasitol ; 216: 107941, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32622940

RESUMO

Distinct antigens have been evaluated with diagnostic purpose for canine and human visceral leishmaniasis (VL), and variable sensitivity and specificity values have been obtained in the assays. In the present study, a Leishmania infantum hypothetical protein called LiHyG, which was identified in an immunoproteomics study in Leishmania infantum amastigote extracts by antibodies in VL dogs sera; was cloned, expressed, purified and evaluated as a recombinant protein (rLiHyG) for the diagnosis of canine and human disease. The recombinant amastigote-specific A2 protein (rA2) and a soluble L. infantum protein extract (SLA) were used as controls. For canine VL, the sensitivity values were of 100%, 57.29% and 48.57%, when rLiHyG, rA2 and SLA were used, respectively, while the specificity values were of 100%, 81.43% and 88.57%, respectively. In addition, AUC values were of 1.00, 0.72 and 0.65, when rLiHyG, rA2 and SLA were used, respectively, while accuracy was of 100%, 72.38% and 75.24%, respectively. For human VL, the sensitivity values were of 100%, 84.00% and 88.00%, when rLiHyG, rA2 and SLA were used, respectively, while the specificity values were of 100%, 58.75% and 73.75%, respectively. In addition, AUC values were of 1.00, 0.76 and 0.83, when rLiHyG, rA2 and SLA were used, respectively, while accuracy was of 100%, 64.8% and 66.6%, respectively. The prognostic role of rLiHyG in the human VL was also evaluated, by means of post-therapeutic serological follow-up with sera samples collected before and six months after treatment. Results showed that treated patients presented significant reductions in the anti-rLiHyG IgG, IgG1, and IgG2 antibody levels, with results being similar to those found in healthy subjects. Testing the rA2 protein and SLA as antigens, lower IgG, IgG1, and IgG2 levels were also found, although they were higher after treatment than those obtained for rLiHyG. In conclusion, results suggested that rLiHyG could be considered for future studies as a diagnostic and/or prognostic marker for canine and human VL.


Assuntos
Antígenos de Protozoários/isolamento & purificação , Doenças do Cão/parasitologia , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Adulto , Idoso , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/genética , Medula Óssea/parasitologia , Biologia Computacional , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito B/química , Feminino , Humanos , Imunoglobulina G/sangue , Leishmania infantum/genética , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/veterinária , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas de Protozoários/química , Sensibilidade e Especificidade , Alinhamento de Sequência , Testes Sorológicos , Baço/parasitologia , Adulto Jovem
14.
PLoS Negl Trop Dis ; 14(7): e0008465, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32706789

RESUMO

BACKGROUND: Leishmaniasis is one of the most important vector-borne diseases and it represents a serious world health problem affecting millions of people. High levels of Leishmania infections, affecting both humans and animals, are recognized among Italian regions. Among these, Sicily has one of the highest prevalence of Leishmania infection. METHODOLOGY/PRINCIPAL FINDINGS: Seventy-eight Leishmania strains isolated from human and animal samples across Sicily, were analyzed for the polymorphic k26-gene and genotypes were assigned according to the size of the PCR products. A multilocus microsatellite typing (MLMT) approach based on the analysis of 11 independent loci was used to investigate populations structure and genetic diversity of the isolated strains. Six L. infantum reference strains were included in the analysis for comparison. Bayesian clustering analysis of microsatellite data showed that all the isolated strains clustered in two genetically distinct populations, corresponding to human and canine isolates respectively. A further subdivision was observed between the two main groups, giving a good correlation between human strains and their geographic origin, conversely canine population showed a great genetic variability diffused in the territory. CONCLUSIONS/SIGNIFICANCE: Among the 78 Leishmania isolates, K26 analysis detected 71 samples (91%) as MON-1 zymodeme, confirming it as the predominant strain in Mediterranean area and 7 human samples (9%) as non-MON-1. MLMT gives important insights into the epidemiology of leishmaniases and allows characterization of different strains to a higher resolution than possible with zymodeme typing. Two main populations presented a strong correlation respect to the different hosts, exhibiting a co-circulation of two distinct populations of L. infantum. The population found in infected humans exhibited a correlation with geographic origin. These clusters could represent a geographically restricted population of strains with the same or related genotypes. This study can contribute to an understanding of Leishmania epidemiology, including the spread of reservoirs and sand fly vectors in the different foci of infection, characterizing parasites within the different hosts.


Assuntos
Doenças do Cão/parasitologia , Leishmania infantum/genética , Leishmaniose Visceral/veterinária , Animais , Doenças do Cão/epidemiologia , Cães , Humanos , Itália/epidemiologia , Leishmania infantum/classificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia
15.
Rev Bras Parasitol Vet ; 29(2): e001120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32490894

RESUMO

This study aimed to determine the seroprevalence, factors associated with seropositivity to Leishmania infection in dogs and spatial analysis in six municipalities in the semiarid region of Pernambuco, Brazil. Blood samples were collected from 462 dogs, 77 in each municipality, and used for serological analysis [dual path platform (DPP®) and enzyme-linked immunosorbent assay (ELISA)]. Clinical signs of dogs were evaluated and associated factors for Leishmania infection were analyzed using robust Poisson regression model. A seroprevalence of 42.8% (198/462, IC: 95% = 38.6%-47.6%) was detected in dogs that tested positive in both tests, ranging from 29.8% to 55.8%, with higher prevalence in the municipality of Cabrobó (55.8%; P = 0.006). About 67% (132/198) of the seropositive dogs showed one or more clinical signs suggestive of canine leishmaniasis (CanL), such as lymphadenomegaly, skin lesions and conjunctivitis, which were associated with seropositivity. High seroprevalence levels were identified in urban and rural areas in all the municipalities, and the buffer for sand flies around cases covered almost these entire areas. Spatial analysis revealed a significant cluster, showing a relative risk of 1.88 in the urban area of Cabrobó. The higher density of seropositive dogs in urban areas indicates the need effective control measures against CanL to prevent the emergence of canine and human diseases.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/epidemiologia , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Análise Espacial
16.
Ann Parasitol ; 66(2): 143-156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32531102

RESUMO

Recently, Leishmania infantum has increasingly been detected in stray cats in endemic regions of the world. Cats have been considered playing a role in the epidemiology of visceral leishmaniosis, an endemic zoonosis in Iran. The studies concerning feline leishmaniosis (FeL) allow the hypothesis that cats can be considered as potential reservoirs. The investigations on Leishmania infection in cats are very few in Iran and therefore we aimed to assess the L. infantum infection in stray cats and its possible role in transmission of the disease to human by direct agglutination test (DAT), ELISA, nested-PCR and confirmation via sequencing and phylogenetic analysis in Fars province, Iran. Whole blood samples were obtained from 174 stray cats. Anti-Leishmania antibodies were detected in the sera using DAT and ELISA. DNA was extracted from the buffy coat of each subject and PCR amplified, targeting Leishmania kDNA gene. PCR results were confirmed by sequence analysis. Prevalence of clinical signs in positive cats was 19.0%. Anti-Leishmania antibodies with different titers were detected in 48 (27.59%) and leishmanial DNA in 36 (20.69%) of the cats. The sequencing of PCR-positive cats revealed the parasite as L. infantum. A high seroprevalence of L. infantum was revealed, with higher levels in males, adult cats, and those living in rural districts and southern zones. Despite the reservoir task of cats in nature is still ambiguous, the high serological and molecular detection of L. infantum in stray cats indicates that cats are regularly bitten by infected sand flies in Fars province, southern Iran, and may have a potential reservoir role in the maintenance of L. infantum in the endemic areas of zoonotic visceral leishmaniosis in Iran. Anyway, Leishmania infection must be appraised in the differential diagnosis of cutaneous or systemic clinical signs in cats.


Assuntos
Anticorpos Antiprotozoários/sangue , Leishmania infantum , Leishmaniose Visceral/veterinária , Animais , Gatos , DNA de Protozoário/sangue , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Leishmaniose Visceral/sangue , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Masculino , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Estudos Soroepidemiológicos
17.
Acta Trop ; 209: 105535, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32450137

RESUMO

Canine visceral leishmaniasis (CVL) has been the theme of several studies given the importance of dog as natural reservoir of the pathogen Leishmania infantum in endemic regions and its role on dissemination of CVL and human visceral Lesihmaniasis (VL). The current immunodiagnosis of CVL has limitations concerning accuracy, specificity and sensitivity. Therefore, improvements are required. rLiNTPDase2 has been previously highlighted as a new recombinant antigen from L. infantum to the CVL diagnosis by ELISA assay (rLiNTPDase2-ELISA). In this study, we aimed to evaluate rLiNTPDase2-ELISA in a Phase II study with 651 dog sera samples, also comparing it with methodologies previously established and used in epidemiology surveillance in Brazil, an endemic country of CVL and VL. The rLiNTPDase2-ELISA using standard control sera showed high capability to distinguish between positive and negative sera, sensitivity of 92.6% and specificity of 88.5%. The test was reproductive and the kappa statistics judgement "substantial agreement". rLiNTPDase2-ELISA does not show cross-reactivity with ehrlichiosis-reagent sera. However, we verified 15.3% of cross-reactivity with Chagas disease-reagent sera. The performance of rLiNTPDase2-ELISA was evaluated using sera samples from vaccinated dogs (Leish-Tec®). The results showed high agreement with parasitological and PCR results (sensitivity of 100.0% and specificity of 91.7%). Furthermore, we compared the performance of rLiNTPDase2-ELISA in CVL-reagent sera samples from endemic areas, which were previously diagnosed using other tests for CVL: immunofluorescent (IFI-LVC-Bio-Manguinhos), IFI-LVC-Bio-Manguinhos coupled to ELISA (EIE-LVC-Bio-Manguinhos) and the Rapid Dual Path Platform® (TR-DPP®-Bio-Manguinhos) coupled to EIE-LVC-Bio-Manguinhos. rLiNTPDase2-ELISA showed high level of concordance with IFI-LVC-Bio-Manguinhos (88.6%) and with IFI-LVC-Bio-Manguinhos coupled to EIE-LVC-Bio-Manguinhos (82.9%) but not with TR-DPP® -Bio-Manguinhos coupled to EIE-LVC-Bio-Manguinhos (33.3%), which casts doubts on the effectiveness of this latest test. In addition, the rLiNTPDase2 antigen adsorbed in 96-well plate was stable enough to be used at least for three months. Taken together, our data confirmed, by Phase II study using hundreds samples, the good potential of rLiNTPDase2-ELISA to be used in the field as a new diagnostic assay for CVL.


Assuntos
Adenosina Trifosfatases/imunologia , Antígenos de Protozoários/imunologia , Doenças do Cão/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Animais , Reações Cruzadas/imunologia , Cães , Leishmaniose Visceral/diagnóstico , Proteínas Recombinantes/imunologia
18.
Rev Soc Bras Med Trop ; 53: e20190525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428174

RESUMO

INTRODUCTION: Canine visceral leishmaniasis (CVL) is a public health problem, and its prevalence is associated with the coexistence of vectors and reservoirs. CVL is a protozoonosis caused by Leishmania infantum that is endemic in the southeast region of Brazil. Thus, vector and canine reservoir control strategies are needed to reduce its burden. This study aimed to verify the CVL seroprevalence and epidemiology in a municipality in Southeast Brazil to initiate disease control strategies. METHODS: A total of 833 dogs were subjected to Dual Path Platform (DPP) testing and enzyme-linked immunosorbent assays. For seropositive dogs, epidemiological aspects were investigated using a questionnaire and a global position system. The data were submitted to simple logistic regression, kernel estimation, and Bernoulli spatial scan statistical analysis. RESULTS: The overall CVL-confirmed seroprevalence was 16.08%. The 28.93% in the DPP screening test was associated with dogs maintained in backyards with trees, shade, animal and/or bird feces, and contact with other dogs and cats, with sick dogs showing the highest chances of infection (odds ratio, 2.6; 95% confidence interval, 2.38-1.98), especially in residences with elderly people. A spatial analysis identified two hotspot regions and detected two clusters in the study area. CONCLUSIONS: Our results demonstrated that residences with elderly people and the presence of trees, shade, feces, and pet dogs and cats increased an individual's risk of developing CVL. The major regions where preventive strategies for leishmaniasis were to be initiated in the endemic area were identified in two clusters.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Gatos , Doenças do Cão/diagnóstico , Cães , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência , Estudos Soroepidemiológicos , Análise Espacial
19.
Rev Bras Parasitol Vet ; 29(2): e016919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428183

RESUMO

Dogs have been implicated as main reservoirs for visceral leishmaniasis (VL) in urban areas. Therefore, studies on this species provide important data for public health. Thus, the objective of the present study was to ascertain the seroprevalence of canine VL (CVL) and the associated factors in the Brejo Paraibano microregion, northeastern Brazil. A total of 409 dogs were sampled from the eight municipalities of the microregion: Alagoa Grande, Alagoa Nova, Areia, Bananeiras, Borborema, Matinhas, Pilões and Serraria. The diagnosis of CVL was made using an enzyme-linked immunosorbent assay (ELISA S7®), through which the prevalence observed was 29.3%. By robust Poisson regression analysis two factors were associated with seroprevalence: illiterate/incomplete elementary owner's education level (prevalence ratio = 1.57; 95% CI = 1.05-2.34; p-value = 0.027) and tick infestation (prevalence ratio = 1.82; 95% CI = 1.27-2.61; p-value = 0.001). It is concluded that the seroprevalence of CVL in the Brejo Paraibano microregion is high. The factors associated with seroprevalence indicated the importance to develop socioeducational actions on the population, and the finding that tick infestation was associated with seroprevalence shows that there is a need for investigation regarding the role of ticks in the epidemiology of CVL.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/epidemiologia , Distribuição Animal , Animais , Brasil/epidemiologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Doenças do Cão/sangue , Doenças do Cão/parasitologia , Cães , Escolaridade , Feminino , Humanos , Leishmaniose Visceral/sangue , Leishmaniose Visceral/veterinária , Masculino , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Infestações por Carrapato/veterinária
20.
Rev Bras Parasitol Vet ; 29(2): e021019, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428187

RESUMO

The midwest region of Brazil has witnessed an increase in the number of cases of human (HVL) and canine visceral leishmaniasis (CVL). The aim of the present study was to evaluate the population's perception of these diseases, factors associated with CVL, its spatial distribution, and the prevalence of anti-Leishmania spp. in 385 dogs, determined using a commercially available immunochromatographic rapid test and confirmed using enzyme-linked immunosorbent assay (ELISA). Of the 385 samples, 54 were positive for CVL and confirmed by ELISA, corresponding to a prevalence of 14%. Knowledge of signs of CVL by tutors (p = 0.038); previous occurrence of CVL in the vicinity (p = 0.022); symptomatic dog(s) (p = 0.014), splenomegaly (p = 0.055), and ear ulcer(s) (p = 0.059) were significantly associated with CVL. The results revealed a significant prevalence of CVL spatially distributed in rural and urban contexts. The association between environmentally related variables and perception and the occurrence of CVL underscores the importance of implementing control and prevention strategies primarily focused on environmental management and health education activities.


Assuntos
Doenças do Cão/parasitologia , Leishmaniose Visceral/epidemiologia , Fatores Etários , Distribuição Animal , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Cidades/epidemiologia , Estudos Transversais , Doenças do Cão/sangue , Doenças do Cão/epidemiologia , Cães , Características da Família , Feminino , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Masculino , Percepção , Prevalência , Análise Espacial , Inquéritos e Questionários
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